BUY 4G4B41 https://www.utsource.net/itm/p/9523656.html

Description: 4G4B41 is a 4-pin DIP (Dual Inline Package) optocoupler. Features: High isolation voltage between input and output Low input current High CTR (Current Transfer Ratio) Low input-output capacitance High speed response Low temperature coefficient High reliability Applications: Isolation of digital signals Isolation of analog signals Isolation of power supply Isolation of control signals Isolation of communication signals Isolation of audio signals (For reference only)